CSW: Not possible to search on Subject queryable for a value that includes spaces

[josegar74]

Loading sample data and searching in CSW GetRecords for Subject = "river basins" doesn't return results, although a metadata with this keyword

<csw:GetRecords xmlns:csw="http://www.opengis.net/cat/csw/2.0.2" xmlns:ogc="http://www.opengis.net/ogc" 
maxRecords="100" outputFormat="application/xml" outputSchema="csw:IsoRecord" resultType="results" 
service="CSW" startPosition="1" version="2.0.2">
  <csw:DistributedSearch hopCount="0"/>
  <csw:Query typeNames="gmd:MD_Metadata">
  <csw:ElementSetName>summary</csw:ElementSetName>

  <csw:Constraint version="1.1.0">
    <ogc:Filter xmlns:ogc="http://www.opengis.net/ogc">
      <ogc:PropertyIsEqualTo>
        <ogc:PropertyName>Subject</ogc:PropertyName>
        <ogc:Literal>river basins</ogc:Literal>
      </ogc:PropertyIsEqualTo>
    </ogc:Filter>
  </csw:Constraint>
</csw:Query>
</csw:GetRecords>

[josegar74]

Applied in 2.6.X branch.

Trunk removed subject field and now is using keyword field (metadata keywords + topic categories).

keyword field is defined untokenized both in config-lucene.xml and index-fields.xsl